The present invention relates to a closing mechanism, for a rotating-type capping machine, for closing the mouth portion of a bottle or other container with a crown cap or similar closure delivered from a supply container, with the closing mechanism being disposed over a bottle support and being adapted, in a vertical axis, to be lowered out of a starting position and to be raised again into this starting position. The closing mechanism has a deformation member for placing the crown cap upon the mouth portion of the bottle and for subsequently fixing the crown cap thereon via permanent deformation of the crown cap while simultaneously pressing the crown cap against the mouth portion of the bottle. The closing mechanism also has a hold-down mechanism that extends centrally through the deformation member and is spring-loaded via at least one spring, with the hold-down mechanism having a surface that faces the bottle support and is provided with a holding means for the crown cap.
A capping machine is known (U.S. Pat. No. 4,205,502) that for closing bottles with closures, namely with crown caps, has a plurality of closing mechanisms, each of which has a hold-down mechanism for placing and pressing a respective crown cap onto the mouth of the bottle that is to be closed, and also has a deformation member for fixing the crown cap on the bottle via deformation. Furthermore, the lower end of each closing mechanism that faces the bottle support is provided with a centering means having a centering opening that, starting from the lower end of the closing mechanism, has a first centering portion that narrows upwardly in a conical manner, as well as a second centering portion that adjoins the first portion and is essentially cylindrical. The bottom end of each hold-down mechanism forms a hold-down surface, and is provided with a holding means (permanent magnet) for holding a crown cap on this surface. The closing mechanisms of the known capping machine are furthermore embodied in such a way that for receiving a crown cap, each hold-down surface is disposed approximately in the same plane as the lower end of the closing mechanism or the centering means. During the process of closing a bottle, in other words during lowering of the closing mechanism out of a starting position onto the bottle that is to be closed, the hold-down mechanism with its surface and the crown cap that is held there are initially held back from the lowering centering means, so that the centering portions of the centering means are shoved over the crown cap that is held on the hold-down mechanism. In so doing, this crown cap is centered in the first conical centering portion of the centering means relative to the closing mechanism in such a way that the central axis of the crown cap is disposed coaxial with the longitudinal axis of the closing mechanism. The crown cap is subsequently fixed in this position in the second centering portion before, during further lowering of the closing mechanism, the crown cap is placed upon the mouth of the bottle that is to be closed, with the mouth region of this bottle then also being surrounded by the centering means, i.e. the mouth of the bottle is disposed in the second centering portion. Immediately following this placement, the crown cap is pressed against the mouth of the bottle via the hold-down spring that acts directly upon the hold-down mechanism as well as via the deformation of the crown cap by the deformation member.
A drawback of this heretofore known capping machine and its closing mechanisms is, among other things, that although a certain centering of the bottle that is to be closed is achieved by the centering portions of the centering means, this centering process is very imperfect since the smallest diameter of the conically tapered first centering portion, and also the diameter of the second centering portion, are somewhat greater than the outer diameter of the crown cap prior to its deformation and hence inherently greater than the outer diameter of the mouth portions of the bottles that are to be closed. Since immediately after the crown cap has been placed upon the mouth of the bottle that is to be closed, i.e. immediately after the crown cap comes to rest against the mouth of the bottle that is to be closed, the hold-down spring already becomes effective and hence presses the crown cap with a great force against the mouth of the bottle that is to be closed, an alignment of the bottle relative to the crown cap is frequently impossible, which results in a defective and unsatisfactory closure of the pertaining bottle.
A further drawback of the heretofore known capping machine and its closing mechanisms is that when looking at the overall operating cycle, the placement of the respective crown cap onto the bottle that is to be closed is effected only relatively late in the cycle, which could lead to losses of filling material or liquid due to filling material foaming up out of the bottles.
It is furthermore known (U.S. Pat. No. 5,040,354) for a capping machine having a plurality of closing elements, to provide a so-called CIP (cleaning in place) cleaning for cleaning and disinfecting the closing mechanisms, with this cleaning being provided in particular for those elements that during the closure process come into contact with the mouth portions of the bottles as well as with the closures themselves, in order to thereby achieve for the material that is dispensed into the bottles an optimum protection against contamination or bacteria, and in particular also yeast, and hence to achieve an optimum shelf life. For this cleaning process, a closure or rinsing cap is provided for each closing mechanism, with this cap, via the use of appropriate arresting means, being adapted to be placed upon the lower end of the respective closing mechanism and to again be removed, whereby after being placed on this cap closes off a rinsing chamber that is essentially formed by the centering opening as well as by the deformation member of the closing mechanism; in addition to the region of the hold-down surface of the hold-down mechanism, this rinsing chamber also encloses all other regions or surfaces that are critical with regard to cleanliness and freedom from bacteria. During the CIP cleaning, a cleaning or rinsing medium (for example rinsing liquid) then flows through this rinsing chamber. The drawback of this is that the connectors as well as the pertaining hoses or conduits for supplying and withdrawing the cleaning or rinsing medium are disposed at the lower end of the respective closing mechanism or at the centering means disposed there.
It is an object of the present invention to provide a closing mechanism that avoids the drawbacks of the known mechanisms and while providing for a simplified construction, ensures an improved functioning.